What are they so sad about?
it's called 'I lied...it wasn't your fault' so my guess is they got in a very heated fight and one of them blamed the other for something terrible
that object on the far right could very well be a tombstone so one of the sisters may have blamed the other for their death at some point, only to retract the accusation while choking back her tears in front of the grave because she realized what she'd done to her own sister by saying such a thing
[](/rosesad) forget that's really sad why did I write that