Both admit they don't typically acknowledge human emotions, but they also have moments where they clearly engage in somewhat emotional moments with the family, or even outside influences (friends, classmates, etc).
That being said, it does seem like Lisa tends to be more consistently withdrawn from the family that Lucy does, and I'm sure it's mostly because she views them more from a scientific perspective; not to mention we've seen that social skills are not her strong point.
Lucy always knows how her siblings don't notice her in Spell It Out.
And she spooks them when she just appears out of nowhere.
Meanwhile, Lisa likes to subject the family to her scientific experiments - particularly Lily.
Does Lola count because of her ego and mean,bratty nature driving people away by scaring them
What is your obsession with Lola's remarks
The thing about Lola is she doesn't surpress her emotions, or intentionally distance herself from her family; Lisa and Lucy both admit to prefer maintain an emotional detachment from others, including their own family.
What do you think?