She's just expressing her feelings...for what she is capable at her age.
My daughter went through a quick phase of that too. I would simply tell her "I L. you no matter what" even when she was in a tantrum. And it made her happy. My telling her that went a long way in making her feel better.
I would recommend "not" telling her things like - you L. her even when she doesn't make you happy-- a child hears "they don't make Mommy happy...." This is a lot for a child to digest...it can possibly make them feel that no matter what they do it's not good enough and that they can never make their Mommy happy. Maybe she tells you "you don't L. me" because she is frustrated, and she can't be "perfect" all the time. A child can never carry that on their shoulders, it's a big burden.
I also would tell my girl, "just try your best. You don't have to be perfect. Mommy always loves you." Also, I would not recommend asking your daughter if she loves you...this is too much for a child to discern. Don't make it her problem to handle. She's too young.
Don't take it personally when your girl tells you "you don't L. me"...but rather, take it as a hint that she needs more attention and possible one on one time with you. Little girls are tender hearted and sensitive...they "need" to know that they are being "heard" and not just having another comment to make them quiet or "behave."
I also would not recommend laughing at her in response... this just teaches them that their feelings don't matter. It's not helpful. Children NEED to know that they matter... that their feelings are being "heard" and cared about. Just like any other person. At this age, their "identity" is forming...they need to know they are loved no matter what....not based on their behavior.
Part of it is the age of development... and perhaps also because you have another baby. Regardless... your girl is obviously searching for some attention and wants to know that Mommy always loves her. Sometimes as Parents, we don't realize that most of the time we say things to our children that are focused on their "naughty" behaviors and trying to correct them all the time... but, we need to concentrate instead on their tender moments and their emotional needs too. Your girl needs reassurance. Don't debate about it with her... don't ask her to define "L.".. she is just a little girl.
It will pass I"m sure...kids this age are dealing with so much..their emotions, cause & effect, social "rules," feelings, tantrums, comparing, independence, sense of self, behaving etc. A little at a time...and with patience...this is the way kids show us they need us. Sometimes, a tantrum and things like this show they have an un-met need. Soon enough, as she matures, she will understand. Just give her time.
Good luck and take care,
~Susan
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