I have used the Moby trailer (I borrowed a friends, the road version) and it was great.
I know you want a four person trailer, but two in the pod and two in the tent (the kids) works for me!
There should a any number of this class of trailer coming on the market used.
Good luck!
https://compactcampingconcepts.com/hbothertrailers.html
Moby1 XC