The toy is not reachable.

[Kumarc]

Kid: The toy is not reachable. It’s too far. Please help me get it.
Father: No, baby. It’s not too far. You can use a stool to reach it.

Please check the phrases of the conversation.

 

[emsr2d2]

Kid: The toy is not reachable I can't reach my toy. It’s too far away. Please help me get it.
Father: No. baby. It’s not too far away. You can use a stool to reach it.

Please check the phrases of the conversation dialogue.

Note my changes above.

If the child is old enough to construct those general ideas, it wouldn't be referred to as "baby". It's unlikely that an adult, let alone a child, would use "The toy is not reachable".
If the child is going to need a stool to reach the toy, it's more likely that they'd say "It's too high [up]" and the dad would say "It's not too high".

 

[jutfrank]

What are you trying to do here, Kumarc? What are you trying to learn?