premmie development vs corrected age

[Salby82]

So I have full time care of my grandson born 28.4 weeks. he is now 6 months earth time but 3.5 months corrected age.
Anyone here been/going through similar that can reassure my concerns. He was smiling and starting to try to giggle a couple weeks ago but then completely shut off for 2.5 weeks. Is now back to engaging and I can get smiles but he definitely doesn't giggle or really goo or ahh. He does make noises but they're more nasal and with his mouth closed. He also EXCESSIVELY chews his hands as if they are going to disappear and this has made it hard to work out which sleeping bag to continue using now.
He is getting better at tummy time but hasn't yet discovered his feet or able to consciously grab any object on purpose. Only this week can purposely put a toy in his mouth if you put it in his hand but forgets that if he moves his hand that it will come out of his mouth. No reaching deliberately for toys, health nurse wants me to start him on solids but I feel like its just too early.
Is this okay and normal? Am i just expecting too much and being paranoid?

No advice, just my full admiration for taking on this baby with complex issues and keeping him out of the care system. All the best to you.

One thing I’ve learned about my preemie is she’s on her own time. She is way behind her peers even at her corrected age, but every so often she achieves that next milestone and it’s awesome.

Do you have physio follow ups etc? They will ensure there’s not any underlying causes.

My son was born at 28+3 with IUGR, the only advice I'll give is let them grow at their own speed. Some things they will be update to date with and others not so much. My son took a very long time to be out o nappies and wouldn't sleep through the night, even now he's a terrible sleeper.