When we went to the hospital to visit my cousin who had just given birth, an OB resident decided to help walk us to where the rooms were and we had small talk because you know.. well, kind of awkward to be walking in silence. Anyway, she asked who gave birth, I said my cousin, and she referred to the baby as being my second cousin. I said, "no, second cousins are children of first cousins." She and my fiancé were not agreeing with me saying that the baby is my second cousin because the mom and I are first cousins. What? But I let it drop since she was a stranger and it really wasn't that big of a deal. But really, I thought that she would know better since she's an OB doctor.

It annoys me whenever this second-cousin thing comes up. Seriously, a lot of people think that if your cousin has a child, they are your second cousin, and your third cousin will be your cousin's child's child. GRRR! J thinks he is second cousins with his dad's cousin. LOL what?? You can't be cousins with your dad's cousin, it just can't happen... unless some weird and confusing intermarriage went whoopydoo in your family. Anyway, I had to explain to him that cousins need to have a common ancestor.. like the same grandparent, or great-grandparent or great-great grandparent.

Siblings = Same parents.

1st cousins = Same grandparents.
You and your cousin have the same lolo and lola, right? 

2nd cousins = Same great-grandparents. Different grandparents.
Referring to your cousin's child and your child because they have the same great-lola and great-lolo (your own grandparents).

You see how it works now?

But wait, what do I call my cousin's daughter? She is my first cousin once removed. Once removed just means you're removing one generation (or the parent's generation) from the line. Like this:

Me -- 1st cousin -- SheShe
                                     |
                           new baby girl

Now we'll remove my cousin SheShe from the chart and see what happens:

Me -- 1st cousin (once SheShe removed) -- new baby girl

New baby girl jumps up one level so our relationship looks like we are 1st cousins, but that's only because we removed SheShe. So.. first cousin once removed.

LOL! If all this is still confusing, just say she's your cousin's baby or, if you choose to like my family since we are tight knit, niece from cousin (so I'm her auntie because my cousins and I are like siblings). Please do not say she is your second cousin because that is a whole generation skipping different.