can you use two bluetooth headsets on a ipad

i want to use my ipad as a media player in our truck for our kids. i ordered two bluetooth headsets but only one would pair at a time. i contact the comoany who said that only one set could be paired up at a time. so its it just that brand can only pair one at a time, or is that in general that only one bluetooth headset can be paired at a time on a ipad?