18 month old sleeping too much??

I know this seems like a dumb question right? My son is 18 months old and he never slept through the night until he was 12 months. Lately (as I'm the last 3 weeks or so) he has been sleeping from his bedtime at 7:30-8pm right through till 11am most mornings and then takes a 3 hour nap in the afternoon!!

Don't get me wrong I'm not complaining that he lets me sleep in when I want to but it just seems like a lot of sleeping for his age. When he is awake he is SUPER active and bright. He speaks, plays and practices his sign language. Learns new things daily and his motor skills are great. He eats like a horse and gives plenty of wet and poop diapers.

Just wondering if any moms out there are in the same boat? I thought maybe growth spurt since he is eating a lot too but I guess I just want so reassurance!

Thanks in advance!