I am the only one in my family that has a MDE account. When I booked, I just typed in my husband and kids names into the reservation - so their names are showing up on all the booking etc.
However, I would like to make an account for my husband so we can have his account to book rides as well (ie I book the LL while he does the VQ or ILL). I tried this, but it didn’t seem to link properly to our reservation and then it looked like there was 2 of him. So I deleted it all because I felt like I messed it up.
It has been a while, but when we faced a similar situation, I had to call, and they were able to join the two “accounts”. One is actually an account, and one is just you managing them. Anyhow, they were able to handle it over the phone.