Anybody transport their kids in a VW camper?

[colsy]

Am desperate not to sell ours, but not sure how compatible they are with kids' car-seats. We've got a three-quarter rock-n-roll bed in the back, with one proper seatbelt and one lap-belt. Would love to hear from anybody who has a similar set-up and who manages to travel with kids. (We're a Devon conversion, so no "upstairs" sleeping, so fitting proper seats in the back isn't an option.)