18 Month Old Will Not Let Me Sit and Eat.

They have those chairs that strap to the chair that have a tray on them and straps to keep them in the chair. They are about $30, and some people sell them on Craigslist.com too.
It'll save you space in your kitchen too!
I babysit a 20 month old and I just put her in a regular booster and she does fine.

I think you could certainly do a booster seat, just make sure it has straps you can still buckle her in to..my 15 month old uses one, and has since she was 12 months. And, as for the fits...mine head to their rooms if they need to pitch a fit, or they can sit nicely at the table. Will she fight..you bet, all out, screaming until you think she will pass out..but then, she will stop. She will realize after a few times that you are serious. The problem is, that right now, she knows that if she gets mad enough, you cave. For the sake of your sanity mind you, something all of us moms understand. But now, it is creating a problem, and so, the pattern must be changed. With mine, I only let them scream in their beds for a minute or two, go in, pick them up, and ask if they are ready to join us. Can she stop crying etc. And try again. I will say, I dont make my 1&2 year olds sit until we are all done, they are allowed to get down, but they are not allowed to ruin dinner for the rest of us. I wish you the best of luck!! I have 4 kids under 8 right now, and am pregnant with another one,so I know what 3 toddlers can do to you! ~A.~

My son is 20 months old and he is in a booster, the kind that straps to a regular chair. It has a tray that you can use, or you can use it without. We use it without the tray and pull him up to the table. If he finishes dinner before me, we let him down, but I do not let him in my lap until I am finished with dinner. If he throws a fit, he throws a fit. It took a few days or maybe a week, but now he knows that mommy gets time to eat too and he doesn't really throw a fit anymore, although he will still come to me to see if I will pick him up.

I say, get a booster, get her at the table for dinner and stand your ground. She'll figure it out and then dinner time will be some much easier on you.

We use the Fisher Price seat that is a high chair but it fits in your chair. So that way they fill like they are eating with the rest of the family. We have used it with my son since he was a baby and I love it since it don't take up extra space in my kitchen/dining room.

http://www.fisher-price.com/fp.aspx?st=2002&e=product...

F.,
Yes she will out grow it along with all the other clingyness she does and will do. These first few years go by faster than you'll ever realize right now and you'll look back and remember when you were everything to her and really miss it. I have a 13 year old, and so many days I wish I could turn that clock around when she was so close to me, now she's in her own little world and mommy isn't allowed too much.
Personally, I'd get the booster chair to put at your table. My 2 year old was like that too (when he was around 1 1/2 yrs), he didn't want to sit in his high chair anymore, so now he sits right next to me at the table. Time to time he still wants to sit on my lap, but for the most part he just wants to be a big boy.
I'm an easy going mom, I know there are moms that are strict and think giving into the child gives them some sort of leverage. Something like this... why fight about it, why make her cry because she wants to sit on your lap, I assure you, one day she'll sit right next to you and not cry once. One day she'll stop wanting you to kiss and hug her, they grow up too fast enjoy this time, you'll never get it back.

Mine is the same. It gets better. I think the strap in chair would probably help. We eat a t a 4 sided table wth 4 chairs. I move her chair over beside mine and let her sit beside me. It helps. Just keep telling her no mamma is eating. She will get it.