Will we fit in a Mazda CX5?

[Kione]

We are going away at Easter and a family member offered to pick us up in that car. Its two adults, DD that will use a booster (if there is a legal alternative let me know!) she is 7, and DS who is 3 months and will be on a car seat; plus the driver.
I am just not sure if we will fit and if not wr will have to arrange for DP to go on the bus.
Thank you!

It's a 4x4 type car so should be fine as long as you're not on the larger side when it would be a squash in the back.

Thanks! I am not large, but not thin... Size 14, DP and I will discover who has the biggest bum!