11.5 week sleep regression?

Lizz
Hi ladies, I'm wondering if anyone else has noticed a significant sleep regression around 11 or 12 weeks? My son was sleeping in 4-5 hour stretches at night until late last week. Now he's waking 3-4 times between 10pm and 7am. Is this a growth spurt? He doesn't seem to be eating more and he's still fairly happy during the day.