Here's a couple of variant you might like -
Cows on my/your side:
https://www.buzzfeed.com/fuelthejourney/cows-on-my-side
Animal Poker:
http://www.tac.vic.gov.au/road-safety/safe-driving/tips-and-tools/games-for-kids
Road trip Bingo:
https://www.autoblog.com/2010/02/25/in-car-games/
My Cow/Dead Cow:
https://roadtrippers.com/stories/10-kid-road-trip-games
My Cow:
https://blogs.agu.org/georneys/2010/11/06/the-cow-game/
