diff --git a/.changeset/rude-groups-shout.md b/.changeset/rude-groups-shout.md
new file mode 100644
index 0000000000..59e4a22aa9
--- /dev/null
+++ b/.changeset/rude-groups-shout.md
@@ -0,0 +1,5 @@
+---
+'@backstage/ui': patch
+---
+
+Improved type safety in `useDefinition` by centralizing prop resolution and strengthening the `BgPropsConstraint` to require that `bg` provider components declare `children` as a required prop in their OwnProps type.
diff --git a/packages/ui/report.api.md b/packages/ui/report.api.md
index 87cea3d387..5922155e93 100644
--- a/packages/ui/report.api.md
+++ b/packages/ui/report.api.md
@@ -118,7 +118,7 @@ export interface AccordionGroupProps
 // @public
 export type AccordionOwnProps = {
   bg?: ProviderBg;
-  children?: ReactNode;
+  children: ReactNode;
   className?: string;
 };
 
@@ -360,7 +360,7 @@ export const BoxDefinition: {
 export type BoxOwnProps = {
   as?: keyof JSX.IntrinsicElements;
   bg?: Responsive<ProviderBg>;
-  children?: ReactNode;
+  children: ReactNode;
   className?: string;
   style?: CSSProperties;
 };
@@ -370,7 +370,7 @@ export interface BoxProps
   extends SpaceProps,
     BoxOwnProps,
     BoxUtilityProps,
-    React.HTMLAttributes<HTMLDivElement> {}
+    Omit<React.HTMLAttributes<HTMLDivElement>, 'children'> {}
 
 // @public (undocumented)
 export type BoxUtilityProps = {
diff --git a/packages/ui/src/components/Accordion/types.ts b/packages/ui/src/components/Accordion/types.ts
index 8895b79086..39ce1ab5be 100644
--- a/packages/ui/src/components/Accordion/types.ts
+++ b/packages/ui/src/components/Accordion/types.ts
@@ -29,7 +29,7 @@ import type { ProviderBg } from '../../types';
  */
 export type AccordionOwnProps = {
   bg?: ProviderBg;
-  children?: ReactNode;
+  children: ReactNode;
   className?: string;
 };
 
diff --git a/packages/ui/src/components/Box/Box.stories.tsx b/packages/ui/src/components/Box/Box.stories.tsx
index f5bc8e5b23..5d60d99872 100644
--- a/packages/ui/src/components/Box/Box.stories.tsx
+++ b/packages/ui/src/components/Box/Box.stories.tsx
@@ -60,6 +60,7 @@ export const Default = meta.story({
       fontWeight: 'bold',
       color: '#2563eb',
     },
+    children: null,
   },
 });
 
@@ -326,6 +327,7 @@ const CardDisplay = ({ children }: { children?: ReactNode }) => {
 };
 
 export const Display = meta.story({
+  args: { children: null },
   render: args => (
     <Flex direction="column" align="center">
       <Flex>
@@ -347,7 +349,7 @@ export const Display = meta.story({
 });
 
 export const BackgroundColors = meta.story({
-  args: { px: '6', py: '4' },
+  args: { px: '6', py: '4', children: null },
   render: args => (
     <Flex align="center" style={{ flexWrap: 'wrap' }}>
       <Box {...args}>Default</Box>
@@ -377,7 +379,7 @@ export const BackgroundColors = meta.story({
 });
 
 export const NestedNeutralColors = meta.story({
-  args: { px: '6', py: '4' },
+  args: { px: '6', py: '4', children: null },
   render: args => (
     <Box {...args} bg="neutral-1">
       <Button variant="secondary">Button (on neutral-1)</Button>
diff --git a/packages/ui/src/components/Box/types.ts b/packages/ui/src/components/Box/types.ts
index f7641d2f27..1b4259099b 100644
--- a/packages/ui/src/components/Box/types.ts
+++ b/packages/ui/src/components/Box/types.ts
@@ -21,7 +21,7 @@ import type { Responsive, ProviderBg, SpaceProps } from '../../types';
 export type BoxOwnProps = {
   as?: keyof JSX.IntrinsicElements;
   bg?: Responsive<ProviderBg>;
-  children?: ReactNode;
+  children: ReactNode;
   className?: string;
   style?: CSSProperties;
 };
@@ -45,4 +45,4 @@ export interface BoxProps
   extends SpaceProps,
     BoxOwnProps,
     BoxUtilityProps,
-    React.HTMLAttributes<HTMLDivElement> {}
+    Omit<React.HTMLAttributes<HTMLDivElement>, 'children'> {}
diff --git a/packages/ui/src/components/Container/Container.stories.tsx b/packages/ui/src/components/Container/Container.stories.tsx
index 44ff6f2d17..e6fbee091b 100644
--- a/packages/ui/src/components/Container/Container.stories.tsx
+++ b/packages/ui/src/components/Container/Container.stories.tsx
@@ -43,6 +43,7 @@ const DecorativeBox = () => (
       backgroundImage:
         'url("data:image/svg+xml,%3Csvg%20width%3D%226%22%20height%3D%226%22%20viewBox%3D%220%200%206%206%22%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%3E%3Cg%20fill%3D%22%232563eb%22%20fill-opacity%3D%220.3%22%20fill-rule%3D%22evenodd%22%3E%3Cpath%20d%3D%22M5%200h1L0%206V5zM6%205v1H5z%22/%3E%3C/g%3E%3C/svg%3E")',
     }}
+    children={null}
   />
 );
 
diff --git a/packages/ui/src/components/Flex/Flex.stories.tsx b/packages/ui/src/components/Flex/Flex.stories.tsx
index 8b3b7af220..ff2aa442ea 100644
--- a/packages/ui/src/components/Flex/Flex.stories.tsx
+++ b/packages/ui/src/components/Flex/Flex.stories.tsx
@@ -70,6 +70,7 @@ const DecorativeBox = ({
         fontWeight: 'bold',
         color: '#2563eb',
       }}
+      children={null}
     />
   );
 };
diff --git a/packages/ui/src/components/Grid/Grid.stories.tsx b/packages/ui/src/components/Grid/Grid.stories.tsx
index d5b83d257d..b3b6957359 100644
--- a/packages/ui/src/components/Grid/Grid.stories.tsx
+++ b/packages/ui/src/components/Grid/Grid.stories.tsx
@@ -36,6 +36,7 @@ const FakeBox = () => (
       backgroundImage:
         'url("data:image/svg+xml,%3Csvg%20width%3D%226%22%20height%3D%226%22%20viewBox%3D%220%200%206%206%22%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%3E%3Cg%20fill%3D%22%232563eb%22%20fill-opacity%3D%220.3%22%20fill-rule%3D%22evenodd%22%3E%3Cpath%20d%3D%22M5%200h1L0%206V5zM6%205v1H5z%22/%3E%3C/g%3E%3C/svg%3E")',
     }}
+    children={null}
   />
 );
 
@@ -94,6 +95,7 @@ export const RowAndColumns = meta.story({
             backgroundImage:
               'url("data:image/svg+xml,%3Csvg%20width%3D%226%22%20height%3D%226%22%20viewBox%3D%220%200%206%206%22%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%3E%3Cg%20fill%3D%22%232563eb%22%20fill-opacity%3D%220.3%22%20fill-rule%3D%22evenodd%22%3E%3Cpath%20d%3D%22M5%200h1L0%206V5zM6%205v1H5z%22/%3E%3C/g%3E%3C/svg%3E")',
           }}
+          children={null}
         />
       </Grid.Item>
       <Grid.Item colSpan="2">
diff --git a/packages/ui/src/hooks/useDefinition/types.ts b/packages/ui/src/hooks/useDefinition/types.ts
index 45ce5e3dc8..2ddc0c88c5 100644
--- a/packages/ui/src/hooks/useDefinition/types.ts
+++ b/packages/ui/src/hooks/useDefinition/types.ts
@@ -47,14 +47,22 @@ export interface ComponentConfig<
 
 /**
  * Type constraint that validates bg props are present in the props type.
- * - Provider components must include 'bg' in their props
+ * - Provider components must include 'bg' in their props and 'children' in propDefs
  * - Consumer components don't need a bg prop
  */
 export type BgPropsConstraint<P, Bg> = Bg extends 'provider'
   ? 'bg' extends keyof P
-    ? {}
+    ? 'children' extends keyof P
+      ? {} extends Pick<P, 'children'>
+        ? {
+            __error: 'Bg provider components cannot have children as optional.';
+          }
+        : {}
+      : {
+          __error: 'Bg provider components must include children in own props type.';
+        }
     : {
-        __error: 'Bg provider components must include bg in props type.';
+        __error: 'Bg provider components must include bg in own props type.';
       }
   : {};