Marriage limit ? Children limit ? Mii limit ?

Hello everyone! I have 17 couples on my island and 9 couples are married. They had 6 children (5 currently living on the island) i have 67 mii in total.

I pretty much had 3 weddings each week but now its been a week and nobody wants to get married anymore or have children. Is it because i have 67 mii ? Is there a limit ?

Thank you :)