Hi, I have another question, hope its not too confusing. I have an existing 3 way switch for the lights in my stairwell. I want to change the single gang box to a 2 gang box and add another switch to power 6 new can lights. Can I disconnect the hot (black) wire and add a pigtail and feed power to my new switch? Hope I worded that right. Thank you much for the help on my last question!

You have to pick up the neutral some how and find out how many amps are being drawn on the circuit now , don't overload the breaker

You have to pick up the neutral some how and find out how many amps are being drawn on the circuit now , don't overload the breaker

There's not much drawn on the circuit, just one light fixture at the bottom of the stairs. Kind of a waste of one circuit, I thought! What do you mean by pick up the neutral? How do I do that?

It all depends on how the switches are wired. If power is being fed to the switch box where you want to add the switch, it can be done. There will also be a neutral in that box

If the power is being fed to the light fixture or the power is being fed to the other 3-way switch, it can't be done. There will be no neutral available to run to the new light.

To determine if power is being fed to the box- If the box only has three wires in it, black white red, it has no "feed" and you have can't do this without adding a feed. If it has a three conductor wire and a two conductor wire, you have to determine if that two conductor wire is power or a "switch leg" ( the wire the goes to the bulb). On the two conductor wire, with the light off, use a tester to see if you have 120 volts between the white and the black. If you do that's your feed. If it only has power when you turn the light on it's a switch leg.

Please allow me to answer your question,Frist the new lights, 14/2 is used as a jumper between each fixture [type of cable NM14/2] the black wire will be used as the hot the white wire will be used as the neutral the bare copper wire is the ground.Starting from light #6to #5one piece of cable will be installed leave about 10" of spare cable at each fixture, at fixture #6 you need a mc connector to hold the cable to the fixture junction box.Once you have the mc connector installed hold the cable up to the connector strip off , around 8" of the outter jacket of the mc cable.Insert the three conductors through the connector ,the fixture will also have three conductors splice black to black {hot/switch leg} white to white [neutral] bare to ground. If you have noticed there are now two cables in fixture #5 ,#4,#3,#2and #1 follow the same action that you have performed on fixture #6 all the way back to fixture #1 The last cable out of #1 fixture will go to your switch . Now for the three way switch,you will need a voltage tester to find the hot/neutral which should come into one or the other of the switch boxes this will determine where the 14/2 from fixture#1 goes, then you can tap off. Now I know that there is more then just the stair lights on that circuirt after you locate the wires you need turn the breaker off and find out what else went out.