Does he still like his ex? 10pts. Help pls?

[Annie]

My crush broke up with his ex 6 months ago.
His ex unfollower all of his social media accounts. However, he is still following her Facebook, twitter and instragram.

His ex is following his sister's instragram. Today, his sister posted the picture of him and her together in the Christmas party. I saw his ex liked the picture.
She liked only the pictures of his sister with him.
She also liked every single pictures on his own instragram

I also saw that he liked 1-2 pictures on his ex instragram yesterday.

My question is:
Does he still like his ex if he is still following her social media accounts?
Do you think she still likes him?

Additional Details
P.S. His ex is friend with his sister.

I know I'm a stalker.. I just want to know. If he still likes her, I'll just walk away and forget about him.
Yes, they dated for 1 and a half year. I think it's pretty long relationship

[SiStAmAx]

I don't think that necessarily means that he likes her...he probably just still cares about her and thinks about her from time to time which is pretty normal, especially if they were together for a long time. Just remember, they must have broke up for a reason and they haven't got back together in the past six months so there is every chance that he doesn't still like her.

[Stefany]

Maybe not, you know maybe he was justtt returning the favor since she liked a lot of his pictures, he might've thought to be nice ill like 1 or 2, to not completely ignore her ; get me? couldve been just that.