Separation Anxiety after birth of second baby

Hi all! I recently had a June 2020 baby and my June 2018 baby got a baby sister 🥰

Unfortunately, my birth was really traumatic and extremely difficult so I ended up in the hospital for six days total. My husband was with me for four of those days and, with covid, my husband couldn't leave (if he wanted to come back) and my son couldn't visit. My son was great with our family friends for the unexpected four days that he was being babysat, but he'd never been away from me for more than ten hours before this.

Since we've been home, he's gotten increasingly needy, which was expected with a new baby; however, he's been waking up every 2-3 hours at night and needing to be cuddled to go back to sleep and yelling "Mama here!" (He actually yells that nearly all day if he doesn't know where I am). He wakes up more than his 5 week old sister 🤦🏻‍♀️

Does anyone have any tips for helping a toddler get through this kind of separation anxiety? TIA ❤️