In addition, the Texas Stars have acquired forward Tyler Kelleher from the Milwaukee Admirals for future considerations.
O’Brien, 25, has recorded three assists in 21 AHL games for Milwaukee this season. The fifth-year pro has skated in 188 career AHL contests with Milwaukee, San Diego and Norfolk, totaling 12 goals and 31 assists for 43 points.
The 6-foot-4, 220-pound native of Hamilton, Ont., was originally selected by Anaheim in the fourth round of the 2012 NHL Draft.
McNeill, 24, has tallied five goals and one assist in 18 AHL games with Texas this season. A fifth-year pro, McNeill has totaled 80 goals and 94 assists for 174 points in 312 AHL games with Texas and Rockford, and played in the AHL All-Star Classic in 2015.
A 6-foot-2, 214-pound native of Langley, B.C., McNeill was originally a first-round pick by Chicago (18th overall) in 2011. He has appeared in two career NHL games, one with Chicago and one with Dallas.
Kelleher, a rookie out of the University of New Hampshire, has seven goals and five assists for 12 points in 26 AHL games with Milwaukee this season.
The 23-year-old native of Longmeadow, Mass., made his pro debut with the Admirals late last season, tallying two assists in six games.