My personal opinion is who cares what you spend. Buy each child something they will like. My opinion kids are taken care of first and best on Christmas. This includes your grandbaby and your 14y/o. You bought a TV for your oldest and $100 of stuff for the baby. Great check that family off your list. You bought something your middle child will like. Have you bought anything for his GF? If not I would pick her up a little something she would like. Then check them off your list. Find out what your 14 y/o wants and buy what you can afford off of this child's list. Check them off, sit back and relax.
My inlaws make a point to tell all of us every Christmas that everyone had the exact same amount spent on them. If there's a difference and they spent less on you, then you will find cash in one of your presents. I'm happy that they think to buy us anything. We are grown adults. I honestly don't care if the same is spent on me as the other adults in the family. The thought of evening out is nice, but not necessary IMO. If I mention I would like something and they are able to buy it for me as a gift, then I love it. I don't care if my sister in law wanted something more expensive and they bought that for her. I don't need (and not to sound selfish but I don't want) fillers, such as t-shirts, socks and other things that are going to clutter up my house in the idea of fairness. They also make a bigger point to tell the grandkids the exact same was spent on all of them. They are only ages 1, 5 and 6. They don't care. If my 5 year old wants a $40 pair of roller skates more than anything, then she's not going to care that her 6 year old cousin got a $100 American Girl doll. At their ages, they want the same amount of presents, although thankfully my DD doesn't seem to care about that either, she's honestly happy with underwear.
I guess what I'm getting at is people, and kids don't think to care about what was spent on who unless they're taught to. This is my main gripe about my inlaws telling the grandkids that exact amounts were spent on all. I don't want my kid to care how much a gift cost, I want her to be happy someone wanted to buy her something, and even better if it's something you really want.
I'm 14 and 16 years older than my brother and sister. I never cared how much was spent on each of us kids at Christmas. I was happy to almost always find my biggest want under the tree. Now that I'm older with my own family the real joy comes in watching DD5 open her presents. Anything I receive is just a bonus on the day.