Thanks for your input, RookieMomHeather. We have a Alpha Omega Elite carseat for Matthew and it doesn't have such straps to use it as a "backpack" so I will have to purchase a cover for it. I saw one that has wheels so the carseat can be dragged around like a luggage. 

Did you board the plane first or last?

With kids you board first. 

We traveled with our daughters to Disneyland when they were 2 1/2 and 14 months.  We didn't travel with carseats (ordered rental car with them) so in the plane my oldest had her own seat and the youngest sat with one of us (try to get a row where it is only your family to not bother anyone else). We made sure they had a good meal before going on so when they were on the plane they slept. I had a small backpack for each with a coloring book, colors and a pretend doctors set (from the dollar store) that they hadn't seen before to play with. They had fun. I had plenty of snacks and they either ate or slept the whole way. For their take off and landing I gave them each a lollipop so their ears wouldn't pop--fine no problem. We opted to take 2 small strollers to transit them around, worked out well and the strollers were light enough to carry.

Disneyland was awesome! We went to only toddler areas and they had a blast. We had a 2 day pass and on the 2nd night we stayed for the fireworks, each still remembers tinkerbell and the castle--great memories!!!!

Be safe and have fun!