It wasn't the same - she knew that. A substitute will never be anything but a poor imitation of the real thing.
But Tara did her best.
She packed lunches, did laundry, helped with homework, assigned chores, established a curfew, grounded her for ignoring the curfew and climbing out of her bedroom window to go visit Spike, arranged a weekly Girls Video Night, made sure she ate vegetables, and hugged her as often as possible.
And no, it wasn't the same.
It never would be.
But substitute or not, Dawn deserved a mother. And it was the least she could do.