Two weapon fighting:
When you take the Attack action and attack with a light melee weapon that you're holding in one hand, you can use a bonus action to attack with a different light melee weapon that you're holding in the other hand. -PHB 195
Pact of the chain feature:
Additionally, when you take the Attack action, you can forgo one of your own attacks to allow your familiar to make one attack of its own. -PHB 107
If I attack with a short sword, can I direct my familiar to make an attack in place of my second bonus-action attack?