How would you describe your normal daily activities?

I would say at the least you would be light active. I don't know any 3 year old that doesn't keep his mother on her toes! I too am a stay at home Mom and I put light active as my normal day.Hope this helped.

I spend equal amounts of time @ work sitting, and then walking, carrying, lifting, standing. If I did that all day I'd day active but as its half and half I've said lightly active.
They say if unsure, go down, because its better to slightly underestimate then overestimate.

(I'm sole-charge of a small business selling fabrics and notions online, so I do some admin work on the computer, the rest is picking and packing orders and cutting fabric, lifting and carrying boxes and rolls of fabric and going up and down stairs.)

When I was a SAHM with little kids I didn't sit all day, but I still would have said sedentary as I wasn't moving about loads. Then just count anything out of the usual as extra exercise (hard out cleaning, running around for more than 5 minutes with the kids, going for a walk)

You're probably at least lightly active. I consider myself sedentary - I write for a magazine and literally just sit at my computer all day and read and/or write.

I doubt that you are able to sit down even remotely that much. That being said, if you're worried about over estimating your calorie burn for the day, put sedentary and then log most of your activities that are not just sitting.

I'd aim for between the two - like allow yourself to go as low as 1200 but up to 1480 if you need it one day. Your maintenance level is probably around 1900-2000 so it'll still be a defecit regardless.