The morning star and bullish abandoned baby are both bullish three-candle reversal patterns, but only the abandoned baby has a middle doji that gaps below both surrounding candles' shadows. Its construction is very similar to the Morning Doji Star, but in the case of the Bullish Abandoned Baby the doji candle gaps below the shadows of the candle lines on either side, which is not the case for the Morning Doji Star.
Both are bullish reversal patterns, but the abandoned baby emphasizes isolation and gaps while the morning star shows gradual stabilization; the difference lies in speed and intensity.