May the road rise up to meet you...
May the wind be always at your back...
May you be in Heaven a half hour before the Devil knows you're dead...
Patt

You won't have a problem mixing pre cuts with fabrics cut from clothing that has been washed many times. That being said, I'm not sure what you mean by 'flat'. Your quilt will 'crinkle' once it is washed, whether you use washed or unwashed fabric. BTW, welcome to the forum.
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Blankets wrap you in warmth, quilts wrap you in love
Marilyn......
My husband's grandmother made quilts for my kids when they were young. She used some new, some old (who knows how old) fabric from clothing. Several of the pieces have shredded and it sure is a pain trying to mend them.
Vernona
I do this all the time and will say that no problems at all. Once it is quilted and washed, no issues.
Sewing mends the soul.
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Do the math; count your blessings
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Unless we are creating we are not fully alive
~ Madeleine L'Engle
I mix them all up as I'm a avid pre-washer of everything but the pre-cuts. No problems here either.
I've even used non-traditional fabric like brocades, silks, and satins in some quilt tops. Those won't stand up as well as regular cottons though, and I will back them with either a fusible interfacing or a muslin foundation.
It sounds as if Vernona's quilts have been loved to pieces! (The very best problem for a quilt to have!) Those can be tough to repair, but I'd probably applique a replacement piece over the top.
Be who you are and say what you feel
because those who mind don't matter,
and those who matter don't mind. - Dr. Seuss
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