In this habeas corpus proceeding, judgment was rendered for the plaintiff, transferring to him custody of his son, Curtis D. Stiwinter, Jr., who is about three and one-half years of age, from the defendants, who were the child’s maternal grandparents and with whom the child had lived since his birth. The defendants have appealed.

While certain corrections and additions to the finding are sought, we can make none which would materially affect the result.

In a case involving the custody of a child, his welfare must be the controlling consideration, and in determining custody much must be left to the discretion of the trial court. It is not bound by expert testimony even if the testimony is uncontradicted. Clearly in this case the court weighed the circumstances with great care. We cannot hold that the trial court could not reasonably conclude that the plaintiff should have the custody of the child. Claffey v. Claffey, 135 Conn. 374, 377, 64 A.2d 540; Claffey v. Claffey, 146 Conn. 104, 109, 148 A.2d 140.

There is no error.

In this opinion the other judges concurred.