Looking for a car seat

Hi glow mamas, I’m looking for a convertible car seat that will fit 2 of them in my backseat with enough space for a 3rd person in the back. I’m also looking for a car seat that can last years like maybe to ages 4-5. I have a 33 pound 2 year old and a 19 pound 6 month old. My daughter is still in a bucket seat but it’s getting too heavy to lug around and my sons chair that he has now, I just feel like it could have better head support on the sides. What chairs do you guys have that you swear by? Thank you in advance 💚