The DGD is 12 and that makes a difference in how she takes correction. Yes, her mother's answer did seem strange to me, but she is around on the other side of the earth from me and maybe emails seem sharper than being there in person would sound.

The DDL just may listen if I offer to help her when we go back. She has more "irons in the fire" than most young mothers and may just be thinking of how to finish the project in a hurry. I may offer to tie it for her or something. I think I will try posting photos of their quilts to let you judge by sight rather than by my explanation. The DGD made a baby quilt for her new niece and the DDL made a double bed sized quilt for a new bunk bed set for her three year old.

Seems strange to quote myself, but it saves time... ;-)

Anyway, maybe the baby blanket will handle the washing with Warm and Natural batting the way it is. However, consider a few more photos of the double sized quilt my DDIL made and let me know what you think.

I personally would want to add some to the larger quilt. She did a lot of work and it would be such a shame to have it spoiled with the first or second washing.

while complimenting them on an outstanding job, express your concerns based on the experience of you and others. Let them know you are not criticizing just suggesting from experience... what they do after that is their choice

I might try something like, "oh, by the way, did I even explain to you about how batting works? Batting needs to be quilted a certain distance to keep it from falling apart when you wash the quilt. The manufacturers recommendations are on the package. Did you happen to read the package the batting came in." I would keep it real light and see if the girls respond. I always make it sound like it's something I forgot to mention in my instructions, so I don't hurt anyone's feelings.

if it was me i would look at said quilt and complement then ask what batting they used because there wasnt alot of stiches and you want to get some batting and then maybe talk about stiches to different batting you have used.

You know what? If you've already broached the subject with them, that should be enough. In time, they may realize that their quilts needed more. They may be happy with them for years to come. Who says a quilt has to last more than one generation? I know you paid for one of them. That was done out of the goodness of your heart. They may, in time, ask for assistance. If they haven't, leave them be. They may be as happy as clams for the time being. Also, they may want to make more in the future. If and when that happens, bring them on shop hops and let them see 'quilting templates' or a design wall that has examples of quilting. They may notice then the difference between theirs and the ones hanging up. Everyone has to start somewhere. Maybe they feel they're 'done' with their quilts. After all, it is theirs, correct? If quilting is something either takes up, they will realize it one day anyway. Just be happy for them.

Good luck as either way well you know the old saying!LOL!!
Let them make their own mistakes and as they get better they will learn from their mistakes and realize oh man I really did make a mistake on that. With my grands I have learned to just let it be and let them learn as they go forward with their sewing/quilting/crafting.

Here's my take on it from the other side of the fence:

If I were 12, or even as just a 'first-time-quilter' I would be more proud of "my" quilt than concerned about technicalities. Let them be happy with their successes. Should they come back and want to continue quilting, they will learn more than just the basics, and their techniques will improve. They'll be able to have the comparison later on, and be able to see their own growth with each project.
Personally, I'd let it go.

ETA: I didn't realize that Cas said pretty much the same thing a bit ago...as perhaps did others on this thread.

I would ask myself which I valued more, the relationships or the quilts.