5th month milestones
Her senses will improve and she can distinguish between bright and subtle colours. She will have better and improved reactions to your sounds and movements. While you talk to her you can feel she is listening to you. She might keep on repeating her giggling sounds or aas and oos. Baby will grasp toys / things with both hands and gripping between fingers.she starts rolling or swaying from side to side.
If you show a toy and hide it and show it back soon, she will gaze and laugh. It means she has started learning that this thing exists even if it was not before her eyes for some time. You can let baby sit with support for a while. Even if your baby misses some of the above actions, there is no need for immediate worry.
Some babies do pick up late and all babies develop at their own rate. But you need to be watchful.