ability score increase:
+2 WIS, +1 CHA
age:
Sirens are considered adults at the same age as most humans but can live up to 500 years.
alignment:
Sirens are free souls and tend to be neutral or chaotic most leaning good but there are smaller tribes of vicious flesh eating sirens.
Size:
Medium
speed:
30ft walking speed in land-form, and in sea-form 15ft walking speed and 40ft swimming speed.
Languages:
Common, Aquan, Elvish