>>You get error because the transaction is not committed yet and the new field is not in the table. Try this:
>>

>>IF NOT EXISTS(SELECT column_name
>>                                     FROM information_schema.columns
>>                                     WHERE table_name = N'AdultInfo' and column_name = N'MaritalStatus')
>>   BEGIN
>>        sp_executesql N'alter table AdultInfo add MaritalStatus char(1) null' -- Only to be in other batch
>>        ALTER TABLE [dbo].[AdultInfo]  WITH CHECK ADD  CONSTRAINT [CK_AdultInfo] CHECK  (([MaritalStatus] IS NULL OR ([MaritalStatus] IN ('W','S','D','M'))))
>>   END
>>

>
>Looks like I need to add EXECUTE in front of the statement.

Yes,
I always forgot it and only when i get error I remember.
Sorry