Hi,
Try the following,
To sort, Instead of year only by month use the following,
Select CONVERT(varchar(11),d.dob,106), DATENAME(MONTH,d.dob), DATEPART(MONTH,d.dob) from driver d order by DATEPART(MONTH,d.dob) asc
To sort by year, date and month use the following,
Select CONVERT(varchar(11),d.dob,106), DATENAME(MONTH,d.dob), DATEPART(MONTH,d.dob) from driver d order by d.dob asc