My 17mo old is suddenly sleepy more??

Long story short he’s always been a bad sleeper.. never slept through the night.. still doesn’t.

But these last couple of days he’s been sleeping from 10pm-10am (he still wakes up 2-4 times in the night though but goes back to sleep)

And he’s ready for a nap around 2pm - he’ll seem very tired - his nap will sometimes last 2 Hrs sometimes less..

Is this normal??

It just seems like he started sleeping more all of a sudden.

Should I be worried?

Also want to add that he had a cold a few days ago.. but he’s recovered from it now, no coughing no fever no other symptoms

TIA