Add the basic movements and jump for the child

Assets/Scripts/Child.cs

@@ -5,27 +5,62 @@ using System.Collections;
 public class Child : MonoBehaviour 
 {
     public float Speed = 10f;
+    public float JumpForce = 10f;
+    public GameObject GroundCheck;
 
     private Rigidbody _rb;
+    private bool _isGrounded = false;
+    private float _xValue;
+    private float _zValue;
 
     void Awake()
     {
         _rb = GetComponent<Rigidbody>();
     }
 
-    public void Move(float xValue, float zValue)
+    void Update()
+    {
+        _isGrounded = IsGrounded();
+
+        Debug.Log(_isGrounded);
+    }
+
+    void FixedUpdate()
     {
         // We move the child depending on the camera orientation
 
         Vector3 forwardDir = Camera.main.transform.forward;
         Vector3 rightDir = Camera.main.transform.right;
 
-        forwardDir.y = 0f;
+        forwardDir *= _zValue * Speed;
-        forwardDir *= zValue * Speed;
+        forwardDir.y = _rb.velocity.y;
 
+        rightDir *= _xValue * Speed;
         rightDir.y = 0f;
-        rightDir *= xValue * Speed;
 
         _rb.velocity = forwardDir + rightDir;
     }
+
+    private bool IsGrounded()
+    {
+        Collider[] colliders = Physics.OverlapSphere(GroundCheck.transform.position, 0.5f, 1 << LayerMask.NameToLayer("Ground"));
+
+        return colliders.Length > 0;
+    }
+
+    public void Move(float xValue, float zValue)
+    {
+        _xValue = xValue;
+        _zValue = zValue;
+    }
+
+    public void Jump()
+    {
+        if (_isGrounded)
+        {
+            _isGrounded = false;
+
+            _rb.AddForce(new Vector3(0f, JumpForce, 0f));
+        }
+    }
 }

Assets/Scripts/ChildController.cs

@@ -14,12 +14,13 @@ public class ChildController : MonoBehaviour
     void Awake()
     {
         InputManager.Instance.PushActiveContext("Gameplay", (int)PlayerNumber);
-        InputManager.Instance.AddCallback((int)PlayerNumber, HandlePlayerInput);
+        InputManager.Instance.AddCallback((int)PlayerNumber, HandlePlayerAxis);
+        InputManager.Instance.AddCallback((int)PlayerNumber, HandlePlayerButtons);
 
         _child = GetComponent<Child>();
     }
 
-    private void HandlePlayerInput(MappedInput input)
+    private void HandlePlayerAxis(MappedInput input)
     {
         if (this == null) return;
 
@@ -48,4 +49,14 @@ public class ChildController : MonoBehaviour
         _child.Move(xValue, zValue);
     }
 
+    private void HandlePlayerButtons(MappedInput input)
+    {
+        if (this == null) return;
+
+        if (input.Actions.Contains("Jump"))
+        {
+            _child.Jump();
+        }
+    }
+
 }