Then DHM is the PrC she wants...
Kobold (venerable, requires 1gp upkeep per day in candy)
Sorcerer 6/DHM 10/some fullcasting PrC 4
Dragonblood sorcerer sub level 1 (change Draconic Heritage for your Familiar)
Loredrake sub (+2 Sorcerer casting)
Greater Draconic Rite
Dragonborn Template (Wings) <- apply this *first* before you tag on DW
Feats:
DW (1)
Draconic Reservoir (3)
Draconic Breath (DHM 1)
Flyby Attack (6)
Draconic feat that gives HP (9)
Draconic Power (DHM 4)
Draconic feat that gives energy resistance (12)
Draconic Legacy (DHM7)
Draconic Armour (15)
Draconic feat (DHM10)
You end up with 7 Draconic feats, which gives you:
+8 to saves vs energy type
energy resistance/24
+16 hp
+1 natural AC
+1 caster level on top of the 3 you already have
3 bonus spells known
1 extra class skill (Hide is good, and Copper gets it, IIRC)
3d6 per spell level breath weapon
You also get:
3/day spell-like ability (any level 1 sorcerer spell)
immunity to sleep and paralysis
flying speed
level 21 sorcerer casting
Amongst other things...
Sub-optimal as heck, but I have made a nigh unkillable sorcerer using that before:
+5 Initiative on top of whatever he already had (he goes first with Improved Initiative and +6 dex bonus and Nerveskitter)
immune to criticals and sneak attacks
uncanny dodge
+10ft land and fly speeds
resist fire/20
swim speed
featherfall, freedom of movement, water breathing and fireshield (hot) on call
blindsense 10ft
He had limited attack options, but with that breath weapon, I dumped what he had into battlefield control like Evard's, Telekinesis, the various Fog spells, and debuff-kills like Ray of Stupid and Shivering Touch.
Turned out to be quite effective. Used the breath weapon against mooks, and then go straight into the big guns on tough monsters. He one-shot dragons at Medium range (love Spectral Hand).