why does increase spell dmg increases skelton dps with added chaos gem?

hi, i was wonder why if i got summon skeleton gem linked with added chaos damage, then put on any equipment that says increased spell damage, the skeleton dps goes up. i checked and with the added chaos damage gem taken off their dps no longer gets raised.

sorry if this has been asked before.

Check if the chaosdamage goes up. If i remember right, the damage of the Added Chaosdamage gem will increase, depending on the gem they support. Summon Skeletons is a spell. That's why the Added Chaosdamage is increased by spelldamage. If you put the gem on a Splitarrow, then the damage would increase, with everything that increases your projectiledamage.

i checked and the chaos damage on the skeletons dosent change, its just their dps. swapping out skeleton with zombie is having the same effect, gonna lvl some added chaos gems

Probably a tooltip error, they are quite common. No bonuses that affect your stats will affect your minions too, ever.