First of all, we would like to stress that an eclipse is a natural phenomenon that was created by Allah Almighty. It is a sign of Allah that has its own path determined for it. Referring to this, Allah Almigthy says, (It is not for the sun to overtake the moon, nor doth the night outstrip the day. They float each in an orbit) (Ya-Sin 36: 40).

Moreover, it is the duty of the Muslim to shun all forms of superstitions from his life and to avoid linking the existence of natural phenomena to certain physical calamities or disabilities that may happen to him. There is a reference to that in the Prophetic Sunnah
, in which Al-Mughirah ibn Shu`bah, may Allah be pleased with him, reported that the the sun eclipsed during the lifetime of the Messenger of Allah (peace and blessings be upon him) on the day whenIbrahim,the Prophet’s son, died. Upon this the Messenger of Allah (peace and blessings be upon him) said the following: “Verily the sun and the moon are two signs among the signs of Allah. They do not eclipse on account of the death of anyone or on account of the birth of anyone. So when you see them (in a state of eclipse), supplicate Allah and observe the Prayer till it is over.” (Reported by Muslim)

Sheikh Ahmad  Kutty, senior lecturer and Islamic Scholar at the Islamic Institute of Toronto, Ontario, Canada, states the following:
Eclipses have scientific explanations which must be sought from the scientists. As far as our religious beliefs about them are concerned the Prophet (peace and blessings be upon him) taught us that the sun and moon are signs of Allah, and their motions and paths are all determined by Allah; they follow the course decreed by Allah. science therefore only confirms what Islam teaches us in such matters. Islam is deadly opposed to holding superstitious beliefs in such matters.

Coming to the issue of whether the child will be born disabled there is nothing stated in the Islamic sources, but if there is any scientific reason for it, you should find it out from physicians in the field. If there is any such connection then it is only one of the causes appointed by Allah; ultimately Allah is the final cause and the power behind all phenomena in the universe.