One-Eighth of a Kilo of Cocaine = 125 grams
Not quite 4 1/2 ounces but almost.
Therefore, the extra 10-12 grams (Depending on how the Ounces are rounded) is refered to as a baby - more than a quarter but less than a half.
"Two grand flat get ya four n a baby"
($2,000 X 8 = $16,000 which is about the price of a kilo)