Why so hard to "let them" grow up?

Where are you going so quickly?

The first steps.

The first "big boy" haircut.

The first independent ride on a two-wheeler.
The first tear-free sleepover.

This mommy watches proud children pass milestone after milestone.  I cheer for them and share their joy, but in my heart the joy is mixed with unspeakable sadness.

Why is it so hard to "let them" grow up?

For me, it seems, there are two reasons for this.

1.  I love them, and I want to protect them from scary big-kid things, and horrible adult things.  Every milestone takes them a step closer to the "real" world.

2.  I am selfish, and I want to keep them for my own enjoyment forever.  Every milestone reminds me that I cannot, was never meant to.

It is not possible to plumb the depths of either of these things in my heart.  Love and sin, joy and sadness are tangled together, and I am not capable of sorting it all out. 

When another milestone is passed, and the joy-ache flares up, a tangled prayer flows out:

Ouch, God, this blessing hurts.  Thank you/Help me.  Purify my mommy love/sin.