---
title: Entity.ChildCollection
framework: realitykit
role: symbol
role_heading: Structure
path: realitykit/entity/childcollection
---

# Entity.ChildCollection

A collection of child entities.

## Declaration

```swift
@MainActor @preconcurrency struct ChildCollection
```

## Topics

### Accessing collection members

- [subscript(_:)](realitykit/entity/childcollection/subscript(_:).md)

### Adding entities

- [append(contentsOf:preservingWorldTransforms:)](realitykit/entity/childcollection/append(contentsof:preservingworldtransforms:)-7g61.md)
- [append(_:preservingWorldTransform:)](realitykit/entity/childcollection/append(_:preservingworldtransform:).md)
- [append(contentsOf:preservingWorldTransforms:)](realitykit/entity/childcollection/append(contentsof:preservingworldtransforms:)-7p4hd.md)

### Removing entities

- [remove(_:preservingWorldTransform:)](realitykit/entity/childcollection/remove(_:preservingworldtransform:).md)
- [remove(at:preservingWorldTransform:)](realitykit/entity/childcollection/remove(at:preservingworldtransform:).md)
- [removeAll(preservingWorldTransforms:)](realitykit/entity/childcollection/removeall(preservingworldtransforms:).md)
- [removeAll(keepCapacity:preservingWorldTransforms:)](realitykit/entity/childcollection/removeall(keepcapacity:preservingworldtransforms:).md)

### Replacing entities

- [replaceAll(_:preservingWorldTransforms:)](realitykit/entity/childcollection/replaceall(_:preservingworldtransforms:)-4mgff.md)
- [replaceAll(_:preservingWorldTransforms:)](realitykit/entity/childcollection/replaceall(_:preservingworldtransforms:)-1vwk4.md)

### Iterating over collection of entities

- [Entity.ChildCollection.IndexingIterator](realitykit/entity/childcollection/indexingiterator.md)

### Describing a collection

- [description](realitykit/entity/childcollection/description.md)

### Manipulating indices

- [startIndex](realitykit/entity/childcollection/startindex.md)
- [endIndex](realitykit/entity/childcollection/endindex.md)
- [index(after:)](realitykit/entity/childcollection/index(after:).md)

### Instance Methods

- [append(contentsOf:preservingWorldTransforms:)](realitykit/entity/childcollection/append(contentsof:preservingworldtransforms:).md)
- [replaceAll(_:preservingWorldTransforms:)](realitykit/entity/childcollection/replaceall(_:preservingworldtransforms:).md)

### Default Implementations

- [CustomStringConvertible Implementations](realitykit/entity/childcollection/customstringconvertible-implementations.md)
- [EntityCollection Implementations](realitykit/entity/childcollection/entitycollection-implementations.md)

## Relationships

### Conforms To

- [Collection](swift/collection.md)
- [Copyable](swift/copyable.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [EntityCollection](realitykit/entitycollection.md)
- [Escapable](swift/escapable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)
- [Sequence](swift/sequence.md)

## See Also

### Relating entities

- [parameters](realitykit/entity/parameters.md)
- [HasHierarchy](realitykit/hashierarchy.md)