"Mi abuelo siempre se levanta a las cinco."
Translation:My grandfather always gets up at five.
That's just the way it is. :-D
To get up = levantarse. It's a reflexive verb (indicated by the se on the end of the infinitive). Levantar means something else if you leave out the reflexive pronouns. (Check a good dictionary. Spanishdict.com is one.)
When telling time, use las before the hours two through twelve, and la before one (una).
A la una = at one (o'clock)
Es la una = It's one (o'clock).
A las doce = at twelve (o'clock)
Son las doce = Its twelve (o'clock).
The articles are not translated.
More on reflexive verbs and telling time: studyspanish.com (Grammar Unit Five).
"Levantar" means to lift or raise something up. This can be used normally with an object, but you can use it with me/te/se when you want to refer to "getting up". "Me levanto" means "I lift myself", or "I get up".
For the second question, imagine that "horas" follows the number of hours. If it's more than one hour, then it's "las". People probably used to always say "hora/horas" when talking about the time. They don't anymore, but the grammar stayed the same.
That's right. So, you are in effect saying "my granddad always gets up at (the hours of) five". When the number is singular, as in a time before two o'clock, you say "a la una y media" (for half past one), and whereas you would say "son las dos y media ahora" for "it's two thirty now" for a time with a number lower than two you don't use the "son las". For "now, it's one thirty pm," you would say "ahora, es la una y media de la tarde". Sorry this is badly explained, but these are very important points for telling the time in Spanish.
Although that is what we are more likely to use as an expression in English (which is why so many people on this page are falling into this trap), here we are talking about something different, namely that "to get up" (levantarse) and "to wake up" (despertarse) are separate activities, and therefore, verbs. So "I get up at seven every morning to go to college" is "me levanto a las siete cada mañana para ir al colegio" but "I wake up at six every morning in summer" is "me despierto a las seis todas las mañanas en el verano".