I had a bore about 8 or 10 months old. i got a baby boar as a buddy, all was peachy for the first 2 months, then i noticed that older boar wasn't happy, and started scratching a lot, the baby bore was growing up and started bully him, i've had them separated since, and older pig is much happier, perhaps because he has all the food to himself, but baby boy is not, he is always calling, yet any time i put them in two runs side by side, baby boar is all evil and scary towards older boar........little poo face!! I'm not saying dont do it, but the first two boars i paired were simular age, as in, both about 8 months, and it was wonderful from straight away....only problem was the second one died...that's why i got a baby boar....well, actually i got 2, figured if one died, first one wouldn't have to go through trauma of bonding again, however the first day one of the two new baby's started being quite aggressive to both, so he was actually separated the 2nd day, but ii couldn't return him, as i got them in a shop, and felt guilty that i was abandoning him, he is still a very very very shy pig, so i'm glad i kept him, cause i just know he would end up passed from pillar to post or just ignored....he will def be newtered and get a wifey, as he is consistently aggressive to both the others....even tried to break into the other run, and only wants to fight....
All i'm saying is it's not easy to know what will happen, sooo many people here have very successful pairs and trio's, i'm just offering another side to the coin.....be prepaired for it not working out, what will you do then? i wish there were rescues here, where i could have taken him to pick a pal!
i'm going to wait, until baby boar is a little older, and maybe past adolescence, and if more attempts fail, i may newter him and pair with a sow, as he is always looking for the others....good luck what ever you decide