Longhorn breeding- new to this

I'm new to cattle! I've taught myself everything I know through youtube, books, and articles and I'm taking a cattlewoman workshop in June to better inform myself and get more hands on experience as well. (I have 30 acres, plenty to forage and graze, water sources, proper fencing, supplemental feed when needed). So still in the beginning stages of a cattle owner.
I have two 13 month old longhorns...bull and a steer. Both are extremely docile. We are getting 2 heifers tomorrow that are ready to breed. I'm working on my calving pen now, but am very curious how long I should keep mama and baby separate from the boys after birth? Do I need to keep both mamas separate from each other as well?
I've read longhorns rarely need assistance when calving but would love to hear someone's experience as well.